<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        div{
            margin-top: 100px;
            text-align: center;
        }
    </style>
</head>
<body>
    <div>
        <button id="start">开始</button>
        <button id="end">结束</button>
        <h1 id="txt">开始抽奖吧</h1>
    </div>
<script>

    var tag=document.getElementById('txt');
    var start=document.getElementById('start');
    var end=document.getElementById('end');
    var timer;
    var list=['库洛米啊','海带鱼丸','鱼丸肉丸','牛肉面汤','海带','哈哈','卡比','拉拉','小波'];
    console.log(list[0]);
    console.log(list.length);
    start.onclick=function(){
        clearInterval(timer);
        timer=setInterval(function(){
            var n=parseInt(Math.random()*list.length);
            tag.innerHTML=list[n]
        },100)
    }
    end.onclick=function(){
        clearInterval(timer);
    }
</script>
</body>
</html>